Leet speak (written as: L33T or 1337) is the most common language on MMORPGs because rude words are not stopped by filters. This language is changing all the time because new words are made and used. A lot of the words use numbers instead of letters but some were made because of typing errors which are now done on purpose. Also, some suffixes are used, such as -age and -ness.

Some of the numbers and symbols used instead of letters are in the table below.